Coverage Report

Created: 2025-01-28 06:58

/src/wget2/lib/fclose.c
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Source (jump to first uncovered line)
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/* fclose replacement.
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   Copyright (C) 2008-2025 Free Software Foundation, Inc.
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   This file is free software: you can redistribute it and/or modify
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   it under the terms of the GNU Lesser General Public License as
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   published by the Free Software Foundation; either version 2.1 of the
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   License, or (at your option) any later version.
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   This file is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public License
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   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
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#include <config.h>
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/* Specification.  */
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#include <stdio.h>
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#include <errno.h>
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#include <unistd.h>
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#include "freading.h"
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#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
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# include "msvc-inval.h"
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#endif
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#undef fclose
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#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
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static int
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fclose_nothrow (FILE *fp)
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{
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  int result;
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  TRY_MSVC_INVAL
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    {
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      result = fclose (fp);
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    }
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  CATCH_MSVC_INVAL
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    {
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      result = EOF;
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      errno = EBADF;
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    }
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  DONE_MSVC_INVAL;
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  return result;
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}
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#else
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0
# define fclose_nothrow fclose
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#endif
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/* Override fclose() to call the overridden fflush() or close().  */
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int
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rpl_fclose (FILE *fp)
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0
{
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0
  int saved_errno = 0;
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  int fd;
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  int result = 0;
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  /* Don't change behavior on memstreams.  */
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0
  fd = fileno (fp);
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0
  if (fd < 0)
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    return fclose_nothrow (fp);
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  /* We only need to flush the file if it is not reading or if it is
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     seekable.  This only guarantees the file position of input files
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     if the fflush module is also in use.  */
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  if ((!freading (fp) || lseek (fileno (fp), 0, SEEK_CUR) != -1)
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0
      && fflush (fp))
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    saved_errno = errno;
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  /* fclose() calls close(), but we need to also invoke all hooks that our
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     overridden close() function invokes.  See lib/close.c.  */
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#if WINDOWS_SOCKETS
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  /* Call the overridden close(), then the original fclose().
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     Note about multithread-safety: There is a race condition where some
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     other thread could open fd between our close and fclose.  */
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  if (close (fd) < 0 && saved_errno == 0)
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    saved_errno = errno;
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  fclose_nothrow (fp); /* will fail with errno = EBADF,
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                          if we did not lose a race */
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#else /* !WINDOWS_SOCKETS */
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  /* Call fclose() and invoke all hooks of the overridden close().  */
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# if REPLACE_FCHDIR
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  /* Note about multithread-safety: There is a race condition here as well.
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     Some other thread could open fd between our calls to fclose and
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     _gl_unregister_fd.  */
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  result = fclose_nothrow (fp);
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  if (result == 0)
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    _gl_unregister_fd (fd);
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# else
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  /* No race condition here.  */
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  result = fclose_nothrow (fp);
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0
# endif
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#endif /* !WINDOWS_SOCKETS */
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  if (saved_errno != 0)
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0
    {
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0
      errno = saved_errno;
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0
      result = EOF;
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    }
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  return result;
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0
}